Defendant was convicted of three felonies as a result of unusually brutal attacks that occurred over a two-day period in September 1984. He was found guilty of first-degree kidnapping under Iowa Code sections 710.1 and 710.2, assault with intent to commit sexual abuse under section 709.11 and third-degree sexual abuse under section 709.4(1).
Defendant’s only assignment of error on appeal is a constitutional challenge to Iowa Code section 701.4 (1983) and Iowa rule of criminal procedure 10(ll)(b)(l) which place on an accused the burden to establish an insanity defense by a preponderance of the evidence. Defendant argues the rule denies him due process under both the federal and state constitutions.
The trial court rejected the defendant’s constitutional challenge and submitted the insanity defense under a jury instruction which embodied the substance of criminal rule 10(ll)(b)(l). Predictably, evidence on the insanity question was conflicting. According to his own evidence the defendant, at the time of the offenses, was disoriented, neglected to take medicine prescribed for a mental disorder, believed he had a computer that could blow up the world, believed he was a physician, owned a large business, and that people were lying to him and stealing from him. His expert witness thought defendant understood the nature and quality of his acts, but only to a degree.
According to the State’s evidence defendant was very much in control of himself, both mentally and physically, during the attack and understood what was happening. He could distinguish right from wrong and knew the nature and quality of his acts. By its verdict the jury of course resolved this factual dispute in favor of the State. The substance of defendant’s challenge is that the trial court’s insanity instruction, and rule 10(ll)(b)(l) upon which it was based, unconstitutionally shifted the burden of proof to the accused.
In State v. Thomas, 219 N.W.2d 3 (Iowa 1974), overruling a century of precedent, a majority of this court adopted the common-law rule this defendant espouses. Id. at 5. Under the Thomas holding the burden was *466placed upon the State to disprove an accused’s claim of insanity.
The legislature responded. It concluded it was more reasonable to require the defendant to prove insanity than it was to have the State prove what was lacking within the mind of the accused. Under Iowa Code section 701.4 and its companion, Iowa rule of criminal procedure 10(ll)(b)(l), the majority holding in Thomas was rejected. It is this legislative rejection which defendant now challenges as unconstitutional.
I. Defendant first turns to the due process clause under the federal constitution. The federal authorities however flatly reject his contention. In interpreting the federal constitution we are not allowed to differ from the holdings of the United States Supreme Court. Michigan v. Summers, 452 U.S. 692, 699-700, 101 S.Ct. 2587, 2592-93, 69 L.Ed.2d 340, 347-48 (1981); McNabb v. Osmundson, 315 N.W.2d 9, 13 (Iowa 1982).
In Leland v. Oregon, 343 U.S. 790, 798-99, 72 S.Ct. 1002, 1007, 96 L.Ed. 1302, 1307 (1952) the court held that a state statute requiring an accused to establish an insanity defense did not violate due process. Leland is still the law. In Rivera v. Delaware, 429 U.S. 877, 97 S.Ct. 226, 50 L.Ed.2d 160 (1976) a challenge to a statute identical to our rule 10(ll)(b)(l) was dismissed for want of a substantial question. And in Patterson v. New York, 432 U.S. 197, 201-02, 97 S.Ct. 2319, 2322-34, 53 L.Ed.2d 281, 286-87 (1977) the court found no due process violation in a state statute which required the accused to prove a defense of “extreme emotional disturbance,” thereby reducing murder to manslaughter.
Defendant’s due process challenge under the federal constitution is without merit.
II. Defendant asks that we consider the same challenge under the due process clause of our state constitution. The due process guaranteed in article I, section 9 of the Iowa Constitution is identical to that in the fourteenth amendment to the United States Constitution. Normally we interpret provisions in our constitution which are similar to those in the federal constitution as being identical in scope, import and purpose. In State v. Boland, 309 N.W.2d 438, 440 (Iowa 1981) we applied this time-honored principle to the due process clauses of the federal and Iowa constitutions.
Of course no rule requires us to apply the principle which accords our constitutional provision the same interpretation which has been rendered to the companion provision in the federal constitution. Defendant urges us to give Iowa’s due process clause an interpretation diametrically opposed to the existing interpretation of the federal clause. But to do so would contradict more than the federal authorities; it would also contradict the clear majority of conclusions of state appellate courts interpreting state constitutions.
Four states have ruled on the question. In Price v. State, 274 Ind. 479, 412 N.E.2d 783 (1980) the Indiana court considered a statute requiring a defendant to prove an insanity defense by a preponderance of the evidence. The court followed the United States Supreme Court’s Leland decision and upheld the statute in the face of both federal and state challenges. Id. at 482-83, 412 N.E.2d at 785. The California supreme court resolved the constitutionality of placing the burden of proof on the issue of insanity on the defendant in People v. Drew, 22 Cal.3d 333, 583 P.2d 1318, 149 Cal.Rptr. 275 (1978). Drew challenged the statute on both state and federal grounds. The California court upheld the constitutionality of the burden, stating the rule did not conflict with due process. Id. at 349-50, 583 P.2d at 1327, 149 Cal.Rptr. at 284. The Maine supreme court discussed proving lack of criminal responsibility in State v. Crocker, 435 A.2d 58 (Me.1981). Crock-er argued that the state must prove his capacity as an element of its case. The court found no merit in the argument. Id. at 72. It held that assigning the defendant “the burden of proving lack of criminal responsibility is permissible under the Maine and United States Constitutions.” Id.
*467The only contrary result was reached by the Colorado supreme court in People ex rel. Juhan v. District Court, 165 Colo. 253, 439 P.2d 741 (1968). The Colorado court rejected the Leland v. Oregon reasoning and found that assigning the burden to the defendant violated the due process clause of the Colorado state constitution. Id. at 745-46. Proof of sanity was held to be an element of the case to be proven by the state.
The presumption of constitutionality is strong. According to the rubric, the defendant has
assumed a heavy burden as the following propositions are well established. Ordinarily statutes regularly enacted by the legislature will be accorded a strong presumption of constitutionality and all reasonable intendments must be indulged in favor of the legislation attacked. One who challenges legislation on constitutional grounds has the burden to negate every reasonable basis upon which the statute may be sustained. Where the constitutionality of a statute is merely doubtful or fairly debatable, the courts will not interfere. Thus a statute will not be declared unconstitutional unless it clearly, palpably and without doubt, infringes the Constitution [authorities].
The judicial branch of the government has no power to determine whether the legislative Acts are wise or unwise, nor has it the power to declare an Act void unless it is plainly and without doubt repugnant to some provision of the Constitution.
State v. Hall, 227 N.W.2d 192, 193 (Iowa 1975).
The presumption of constitutionality arises, not because we do not take the constitution seriously, but because we do. All three branches of government were commissioned by the same constituency. It is the primary function of the legislative branch to declare what the law shall be. When the people acting through that branch have made such a solemn declaration, our scheme of government calls upon the judicial branch to strike it down only with profound reluctance and only when it clearly falls outside the basic charter of government. The provision challenged here clearly withstands scrutiny under this standard.
This court is in a poor position to subscribe to defendant’s claim that the burden under the rule is so fundamentally unfair as to be unconstitutional. During most of our state’s history we preferred the burden under the challenged rule and adopted it as a matter of common law. When we changed the rule in Thomas in 1974 our decision was five to four, with no claim by any member of the court that a constitutional question was involved.
It is readily apparent why we felt no constitutional impetus for the holding in Thomas. Insanity is a subjective condition bound up inside the mind of the accused. In raising the insanity defense an accused claims a mental condition at variance with what is normal and expected. See State v. Snetken, 245 N.W.2d 308, 310-11 (Iowa 1976) (presumption of sanity revived in formerly insane person by medical facility director’s notification that accused’s mentality was restored).
The assignment is without merit.
III. Defendant attempts to argue as a separate contention that rule 10(ll)(b)(l) unconstitutionally requires an accused to prove a claim in negation of the mens rea element of the offense. The gist of the contention, as we understand it, is that the concept of sanity means the same thing as capacity to commit the crime. In those offenses, such as the ones involved here, where a criminal intent is an element, the defendant would append sanity to the showing required of mens rea. The result would be to add sanity as an element in all criminal intent crimes. Most crimes would be included.
The practical thrust of the contention is identical to the one we have already rejected. It must be remembered that the purpose of the challenged rule was not to shape the elements of various crimes. Rather, its purpose was to establish the applicable legal standard for deciding, in *468the face of evidence of mental impairment, who should answer for their crimes. State v. McVey, 376 N.W.2d 585, 588 (Iowa 1985). Those who should answer could be selected without regard to the elements of various offenses.
Defendant’s argument is based on two premises: (1) mental capacity to commit the offense is an element of the crime; and (2) sanity is the same thing as capacity to commit the crime. Defendant concludes from these premises that the rule unconstitutionally places the burden of disproving an element on him. We disagree with defendant’s first premise and are unwilling to adopt his second. And we reject the assignment because we think the premises, even if adopted, would not lead to his conclusion.
Defendant’s argument comes down to a complaint that the State should not escape the burden of proving an element of the offense. Elements, however, are promulgated by the legislature because all Iowa crimes are statutory. In the prior divisions of this opinion we have held that rule 10(ll)(b)(l) otherwise passes constitutional muster. This being true the legislature was free, if it chose, to subtract this element from the offense. Defendant’s challenge would fail even if the element of the offense here was in fact subtracted from the proof required by the state.
The assignment is without merit.
AFFIRMED.
All Justices concur except LAVORATO, J., who dissents, and NEUMAN, J., who takes no part.